Fig. 2.
Lapatinib inhibits in vivo growth of syngeneic-grafted tumor cells. Eight-week-old MMTV-erbB-2 transgenic mice were subcutaneously injected with 1 × 106 78617 cells. The animals were then treated with 100 mg/kg/day lapatinib or vehicle control for 14 days. Tumor growth was monitored three times a week for three weeks. a Average tumor volumes in the control and lapatinib treatment groups are presented as means ± S.E. Images of syngeneic tumors after 14 days of lapatinib treatment are shown in (b). c Syngeneic tumor-grafted control and lapatinib (100 mg/kg/day for 14 days)-treated mice were injected with BrdU 90 min before euthanization Then tumors were excised and prepared for IHC analysis of BrdU nuclear incorporation. BrdU-positive cells are indicated by brown staining. d TUNEL staining of apoptotic cells is indicated by brown staining in tumor tissues from control and lapatinib-treated mice. BrdU-positive and TUNEL-positive cell percentages are graphed as the means ± S.E. (** p < 0.01)